Many people think that a choppy market–up one day, down the next–like the one we seem to be caught in at the moment yields no information, either about individual stocks or the market as a whole.

This is a mistake. It’s not as bad as failing to check your portfolio when the market is roaring ahead (everyone checks his stocks all the time in this situation, though) or falling through the floor (when even profressional sometime can’t bring themselves to look). Still, it’s a mistake.

You don’t necessarily want to make portfolio changes, but you do want to find out two things:

–is your portfolio is geared for an up market or a down one? …that is, whether your stocks perform well on up days and badly on down days, or vice versa.

It also possible that you have stocks that outperform all the time, or none of it. The former are probably ones to add to, the latter to consider showing the door.

–how your individual stocks are doing.

The checking is relatively easy. I use Google Finance, but any other online service will do as well.

Get the chart page and create a chart of the S&P 500 (.inx on Google). Then enter your stocks/mutual funds/etfs for comparison, three or four at a time. You can vary the charting period to be: one day, a specific starting and ending date, or year to date. Look for overall performance, performance during up periods and performance during down periods.

You can also try longer time periods, like three months, six months, a year or the entire time you’ve owned the stock.

Results can be surprising. I’ve been doing thisexercise just before writing this post. I located one clunker that I’d been thinking of as matching the market over the past six or seven months, but it’s been a chronic underperformer. Embarrassing, maybe, but at least I now know I have a problem to fix.